I had a very similar issue after upgrading to 2022.4, although that are now resolved. Ricardo and Musco were kind enough to help me with that.
In my example, looking through /var/log/rhn/rhn_taskomatic_daemon.log was enough to identify the specific issue, which was a bug introduced with that version relating to the database. It's probably not that, but there should be more useful information than simply "check null".
You can also review and manually trigger this from the Uyuni webui; Admin -> Task Schedules: Click on mgr-update-reporting-bunch and you can see when it was run and its exit status. You can force a fresh run with the above, and if you're watching the above log it might simplify finding the error.
From: Crefeld, Tobias LKV Bayern e.V. Tobias.Crefeld@lkv.bayern.de Sent: 27 July 2022 11:08 To: 'email@example.com' firstname.lastname@example.org Subject: [EXTERNAL EMAIL] Subtask mgr-update-reporting failed.
recently I upgraded the Uyuni system from 2021.07 to 2022.06. Several tests were successful so I'm not sure if the current problems come from the update.
There are two issues:
1. Since Uyuni's update several clients don't check in any more. All of them are using "Push via SSH tunnel" or "Push via SSH" as contact method. Salt clients with contact method "Default" (SLES15-SP3) run fine. Client OS is "openSUSE Leap 15.1 x86_64" or "SUSE Linux Enterprise Server 12 SP5 x86_64". There is no "configuration" or scripting - the only target is to monitor the patch level and provide repositories. 2. After a reboot of the Uyuni host I was sent an email with this content:
"Taskomatic bunch mgr-update-reporting-bunch was scheduled to run within the update-reporting-default schedule.
Subtask mgr-update-reporting failed.
For more information check null." (Checking "null" wasn't successful)
Any hints are welcome!
Regards, Tobias Crefeld.